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Sunday, April 29, 2012

Odds of Finding Alien Life Boosted by Billions of Habitable Worlds

Everything is possible in the universe except the possibility of life evolving on its own, that is not possible because all life forms are created "intentionally" for the environments which that life will live in, exist in. "All" zones around suns, red dwarfs or whatever, are habitable for whatever life forms that are created to live on them. That is such a difficult idea for scientists wearing 3D glasses to see and understand. For some of them everything revolves around 3 dimensional concepts or they don't revolve at all. Silly people.

A new estimate of the number of
habitable planets
orbiting the most common type of stars in our galaxy could have huge
consequences for the search for life.

According to a recent study, tens of
billions of planets around red dwarfs are likely capable of containing
liquid water, dramatically increasing the potential to find signs of life
somewhere other than Earth.

Red dwarfs are stars that are fainter,
cooler and less massive than the sun. These stars, which typically also live
longer than Class G stars like the sun, are thought to make up about 80 percent
of the stars in the Milky Way, astronomers have said.

A second look

Red dwarfs generally have not been
considered viable candidates for hosting habitable planets. Since red dwarfs are
small and dim, the habitable zone surrounding them — the
region where an orbiting planet's surface water can remain liquid — is
relatively close to them.

"The habitable zone would be very, very
small. Consequently, the chances that you would actually find any planet at the
right distance from the sun to be attractive to life was likely to be small,
too," said Seth
Shostak, a senior astronomer at the Search for Extraterrestrial Intelligence Institute in
Mountain View,
Calif. [The Strangest Alien Planets]

But the study, based on data from the
European Space Agency's HARPS spectrograph in Chile, used a sample of 102 red
dwarfs to estimate that 41 percent of the dim stars might be hiding planets in
their habitable zone.

"The number of habitats might increase by a factor of 8 or 10," Shostak told
SPACE.com.Difficult environments
One of the largest concerns about planets circling red dwarfs is radiation. A
red dwarf's habitable zone is generally closer to it than Mercury is to our sun,
so a planet there would receive a strong shock of particles when storms erupted
on the red dwarf.
"They could essentially give everything on the surface that's exposed to the
sky ... a heavy dose of radiation," Shostak said. "It could be fatal."
However, if the alien planet had a magnetic field, this could provide some
protection. So, too, could an ocean of water. Life that evolved beneath an ocean might be shielded from the
brunt of the radiation.
(That's not necessarily good news for SETI, which searches for signals from
extraterrestrial life. "We're not sure intelligent life, if under water, will be
building radio transmitters and we're going to hear from them," Shostak said.
"But it's possible.")

Another problem with planets tightly bound
to their host star is a phenomenon known as tidal locking, in which one side of the world is perpetually
turned toward the sun and receiving almost all of the heat.

But this isn't considered as big of a
problem now as it had been.

For one thing, research over the past few
years has indicated that the presence of other planets can ease the grip of the
parent star, keeping a planet from being perfectly stagnant.

Furthermore, if the planet has an
atmosphere, it might also boast wind, which could move the hot atmosphere to the
dark side and the cool atmosphere to the sunlit side.

"Clearly, if it's too cold on one side and
too hot on the other, somewhere in the middle there's that lovely Goldilocks
zone where everybody wants to build their condos," Shostak said.

Even with these challenges, the sheer
influx of tens of billions of potentially habitable planets improves the chances
of finding alien life.

"SETI is looking for Mr. Right or maybe Ms.
Right, depending on your point of view," Shostak said. "It helps to find out
that there's 10 times as many candidates as there were before."